CVE-2023-28771: Zyxel Multiple Firewalls OS Command Injection Vulnerability

Published Apr 25, 2023
·
Updated

Zyxel ATP, USG FLEX, VPN, and ZyWALL/USG firewalls allow for improper error message handling which could allow an unauthenticated attacker to execute OS commands remotely by sending crafted packets to an affected device.

Other sources

Improper error message handling in Zyxel ZyWALL/USG series firmware versions 4.60 through 4.73, VPN series firmware versions 4.60 through 5.35, USG FLEX series firmware versions 4.60 through 5.35, and ATP series firmware versions 4.60 through 5.35, which could allow an unauthenticated attacker to execute some OS commands remotely by sending crafted packets to an affected device.

Affected Software

82 affected components
Zyxel Multiple Firewalls
Zyxel firewall
All of the following
Zyxel Atp100 Firmware>=4.60<5.36
Zyxel Atp100
All of the following
Zyxel Atp100w Firmware>=4.60<5.35
Zyxel Atp100w
All of the following
Zyxel Atp200 Firmware>=4.60<5.36
Zyxel ATP200
All of the following
Zyxel Atp500 Firmware>=4.60<5.36
Zyxel ATP500
All of the following
Zyxel Atp700 Firmware>=4.60<5.36
Zyxel Atp700
All of the following
Zyxel Atp800 Firmware>=4.60<5.36
Zyxel ATP800
All of the following
Zyxel Usg Flex 100 Firmware>=4.60<5.36
Zyxel Usg Flex 100
All of the following
Zyxel Usg Flex 100w Firmware>=4.60<5.36
Zyxel Usg Flex 100w
All of the following
Zyxel USG FLEX 200 firmware>=4.60<5.36
Zyxel USG FLEX 200
All of the following
Zyxel Usg Flex 50 Firmware>=4.60<5.36
Zyxel USG FLEX 50
All of the following
Zyxel USG FLEX 500 firmware>=4.60<5.36
Zyxel USG FLEX 500
All of the following
Zyxel Usg Flex 50w Firmware>=4.60<5.36
Zyxel Usg Flex 50w
All of the following
Zyxel USG FLEX 700 firmware>=4.60<5.36
Zyxel USG FLEX 700
All of the following
Zyxel Vpn100 Firmware>=4.60<5.36
Zyxel Vpn100
All of the following
Zyxel Vpn1000 Firmware>=4.60<5.36
Zyxel Vpn1000
All of the following
Zyxel Vpn300 Firmware>=4.60<5.36
Zyxel Vpn300
All of the following
Zyxel Vpn50 Firmware>=4.60<5.36
Zyxel Vpn50
All of the following
Any of the following
Zyxel Zywall Usg 310 Firmware>=4.60<4.73
Zyxel Zywall Usg 310 Firmware=4.73
Zyxel Zywall Usg 310
All of the following
Any of the following
Zyxel Zywall Usg 100 Firmware>=4.60<4.73
Zyxel Zywall Usg 100 Firmware=4.73
Zyxel Zywall Usg 100
Zyxel Atp100 Firmware>=4.60<5.36
Zyxel Atp100
Zyxel Atp100w Firmware>=4.60<5.35
Zyxel Atp100w
Zyxel Atp200 Firmware>=4.60<5.36
Zyxel ATP200
Zyxel Atp500 Firmware>=4.60<5.36
Zyxel ATP500
Zyxel Atp700 Firmware>=4.60<5.36
Zyxel Atp700
Zyxel Atp800 Firmware>=4.60<5.36
Zyxel ATP800
Zyxel Usg Flex 100 Firmware>=4.60<5.36
Zyxel Usg Flex 100
Zyxel Usg Flex 100w Firmware>=4.60<5.36
Zyxel Usg Flex 100w
Zyxel USG FLEX 200 firmware>=4.60<5.36
Zyxel USG FLEX 200
Zyxel Usg Flex 50 Firmware>=4.60<5.36
Zyxel USG FLEX 50
Zyxel USG FLEX 500 firmware>=4.60<5.36
Zyxel USG FLEX 500
Zyxel Usg Flex 50w Firmware>=4.60<5.36
Zyxel Usg Flex 50w
Zyxel USG FLEX 700 firmware>=4.60<5.36
Zyxel USG FLEX 700
Zyxel Vpn100 Firmware>=4.60<5.36
Zyxel Vpn100
Zyxel Vpn1000 Firmware>=4.60<5.36
Zyxel Vpn1000
Zyxel Vpn300 Firmware>=4.60<5.36
Zyxel Vpn300
Zyxel Vpn50 Firmware>=4.60<5.36
Zyxel Vpn50
Zyxel Zywall Usg 310 Firmware>=4.60<4.73
Zyxel Zywall Usg 310 Firmware=4.73
Zyxel Zywall Usg 310
Zyxel Zywall Usg 100 Firmware>=4.60<4.73
Zyxel Zywall Usg 100 Firmware=4.73
Zyxel Zywall Usg 100

Event History

Apr 25, 2023
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionSeverityWeakness
Data Sourced
via NVD·02:15 AM
DescriptionSeverityWeaknessAffected Software
May 31, 2023
Known Exploited
via CISA·12:00 AM
Nov 13, 2023
News Published
02:33 PM
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Frequently Asked Questions

1

What is CVE-2023-28771?

CVE-2023-28771 is a vulnerability that allows an unauthenticated attacker to execute OS commands remotely on Zyxel ATP, USG FLEX, VPN, and ZyWALL/USG firewalls.

2

How can an attacker exploit CVE-2023-28771?

An attacker can exploit CVE-2023-28771 by sending crafted packets to the affected Zyxel firewall devices.

3

Which Zyxel firewall products are affected by CVE-2023-28771?

Zyxel ATP, USG FLEX, VPN, and ZyWALL/USG firewalls are affected by CVE-2023-28771.

4

How severe is CVE-2023-28771?

CVE-2023-28771 is a critical vulnerability that allows remote code execution on affected Zyxel firewall devices.

5

Is there a fix available for CVE-2023-28771?

Yes, Zyxel has released a security advisory with mitigation measures for CVE-2023-28771.

Company

Resources

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